Have they shown any evidence for string theory or brane theory, in spite of decades and possibly billions of dollars in science funding spent on the adventures? Have string theory and brane theory shown any predictive power?

I'll let those who know those fields answer for themselves.

My question to you still remains.

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Smart people believe weird things because they are skilled at defending beliefs they arrived at for non-smart reasons. --Michael Shermer

The history of religion is a long attempt to reconcile old custom with new reason, to find a sound theory for an absurd practice. --Sir James George Frazer

I dont think I will put a time line on this just a clean way of thinking how this all might have happened. In 1995 NASA and the good old bubble telescope made some interesting discoveries as to the theory of the big bang. as one might try to imagine the universe was very hot as a result of particles of both matter and antimatter rushing apart in all directions as it began to cool at around 10^-43 seconds after the BB there existed an almost equal yet asymmetrical amount of matter and antimatter as all of these materials are created together they collide and destroy one another creating pure energy. Fortunately for us there was an asymmetry in favour of matter.

Using the astro-2 observatory they were also able to confirm one of the requirements for the foundation of the universe. They were able to detect primordial helium. Oh great I just opened a can of worms for jokes. Hydrogen and helium.

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The classical man is just a bundle of routine, ideas and tradition. If you follow the classical pattern, you are understanding the routine, the tradition, the shadow, you are not understanding yourself. Truth has no path. Truth is living and therefore changing. Bruce lee

And again I'll let the modern world of theoretical physics speak for itself insofar as what it chooses to freely label legitimate "scientific theory": Modern theoretical physics (but because the field and its practitioners so often have so little direct connection with empirical reality, I view it and them respectively as "mathematical philosophy" and "mathematical philosophers") is patently happy to label as "theory" a succession of unevidenced, nonpredictive and endlessly malleable speculations, such as general relativity theory, Kaluza-Klein theory, String theory, M-theory and now of course Bubble theory.

And again I'll let the modern world of theoretical physics speak for itself insofar as what it chooses to freely label legitimate "scientific theory": Modern theoretical physics (but because the field and its practitioners so often have so little direct connection with empirical reality, I view it and them respectively as "mathematical philosophy" and "mathematical philosophers") is patently happy to label as "theory" a succession of unevidenced, nonpredictive and endlessly malleable speculations, such as general relativity theory, Kaluza-Klein theory, String theory, M-theory and now of course Bubble theory.

General relativity failed to predict the Hubble expansion. General relativity failed to predict Zwicky's discovery of anomalous rotation speeds of galaxies and larger observed structures, necessitating the ad hoc invocation of dark matter in order to rescue the theory. General relativity failed to predict the discovery a decade ago of the accelerating universe, necessitating the ad hoc invention of dark energy in order to rescue the theory.

Incidentally, it's a matter of historical record that Mercury's anomalous perihelion shift, often pointed to as the first and most concrete physical prediction of general relativity, was actually a postdiction. Einstein and his mathematician coauthors and indeed all the physics world of that era were well aware of the anomaly and were looking for an explanation. The form of general relativity announced as "predicting" the anomaly was actually the fourth or fifth version specifically tailored to explain it mathematically. Of course it's perfectly correct to make sure one's physical theory jives with physical observation, but to then claim that the theory predicts the incorporated phenomenon is just lawyer-like dissembling.

All scientific theories change when new discoveries are made. This is true in every field of science. Classical mechanics, organic chemistry, quantum mechanics, electricity and magnetism, general relativity, evolution have been continually modified to better fit the observations since they were first proposed. This is a good thing.

General relativity is the best theory yet devised on the way the universe behaves on a big scale. You need to go take some college level science classes.

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How do you define soul?"A baseless assertion by simple-minded, superstitious individuals" -Starstuff

Can I ask the doubters here to answer if the big bang didn't happen then how do they explain Lithium?

For those who don't know Lithium is a very common element (In the grand scheme of things). But it is universally spread, and can not be created by any know means. In fact stars find this element to be very fragile and as a result tasty (they break it down to use it's parts in other reactions) and they don't make it. Current logic says it was created in the big bang, since it's on a dowward spiral to elemental exinction.

thanks for the post Admin 1.this article is obviously an argument for creation.I cannot reconcile this argument, unfortunately.wave-particle duality and the record of time stored with particles (?communication?) precludes my stubbornness.(notice the plural usage)this article assumes that all the properties of the universe were known which flies in the face of wave-particle duality.

Have they shown any evidence for string theory or brane theory, in spite of decades and possibly billions of dollars in science funding spent on the adventures? Have string theory and brane theory shown any predictive power?

String Theory makes many predictions, but most of them are not yet (or in the foreseeable future) verifiable in a technological sense. The strings themselves could be directly observed, theoretically, but that is farrrrrrrr beyond our current technological ability. ST is also quite complex in that it speaks of the most minuscule quanta for which science is not yet able to understand the theory in enough detail to say "ah, if that's so, then [easily verifiable test] can be empirically tested".

Nevertheless, we can be sure it makes some predictions that CAN be tested. The LHC should be able to test supersymmetry (a necessary component of ST) and verify if a) supersymmetry exists, and b) if the electroweak force decouples at the predicted energies (predicted by both ST and AdS/CFT.)

There are also testable implications of ST, and while these tests would not verify ST, they could falsify it. For example: Gravitons according to ST are closed-loop particles, which means that they are NOT bound to our spacetime. If that is true, then that explains why gravity is so weak compared to the other forces...it's actually NOT as weak, it's just that we only perceive gravity within our spacetime plane. This is testable, because at extremely small distances gravity would appear much stronger. Gravitons leaving our plane would still have a radius of interaction, even if they were slightly off our plane. Test for this effect are currently underway.

There are probably MANY more tests that can be performed on ST, once it is better understood and constrained. No test, no observation yet performed has indicated that ST is NOT true.

I'll go ahead and remind the world that hideousmonster is too chickenshit to correct his own mistake, that I pointed out to him most recently here. He won't correct himself when he's wrong, even when it is pointed out to him and the mistake is clear as can be. This is Day 14.

I'll go ahead and remind the world that hideousmonster is too chickens**t to correct his own mistake, that I pointed out to him most recently here. He won't correct himself when he's wrong, even when it is pointed out to him and the mistake is clear as can be. This is Day 14.

I actually revert to quick skimming when confronted by long posts written in the ad hominem mode, Davedave, so I don't know about and don't care what sort of cowardice you're accusing HM of. But I think he explained his position well enough on several fronts. When things devolve to personal attacks it's quite probably the wise person who drops out. It would have been wise of everyone to just drop out of that long long fag thread at old WWGHA. And another point: It takes zero courage and zero background knowledge to defend pop culture myths such as the deification of overt plagiarist Albert Einstein, and it takes zero courage or knowledge to defend unevidenced many-angels-dancing-on-pinheads imaginings such as we find in string theory, with its multiple dimensions comprised of curled up, massless black holes. Again, it isn't necessary that we all learn the calculus of tensors to speak intelligently of the weak physical/epistemological foundation of general relativity and its poor record of prediction, in spite of the endorsement of the pop press and most pop science anthologies.

...only recently have we even realized that the apparent expansion of the area of space which immediately surrounds us, looks like it might be accelerating. It has barely been more than ten years since that idea was thought idotic by most, because it conflicts with the previously established laws of gravity. Are you telling me that physicists can make such an enormous blunder as this, and still expect people to trust them when they tell us what the universe looked like over 13 billion years ago, when we know they rely on regularly-reimagined "standard" model of theoretical physics?...

Again, it isn't necessary that we all learn the calculus of tensors to speak intelligently of the weak physical/epistemological foundation of general relativity and its poor record of prediction, in spite of the endorsement of the pop press and most pop science anthologies.

trustno1,

It is necessary to do that it you specifically claim to understand the evidence. Doubt of Big Bang is not the issue here. It is that he claimed he understood the evidence for it. He doesn't actually understand the evidence for it. In fact, he hasn't even examined the evidence for it. That's my problem. He shouldn't say he possesses understanding that he does not possess.

Are you telling me that physicists can make such an enormous blunder as this, and still expect people to trust them when they tell us what the universe looked like over 13 billion years ago, when we know they rely on regularly-reimagined "standard" model of theoretical physics?...

The Standard Model is .... wait for it.... a model.

It is not a theory. It's basically a table of everything we know about subatomic particles and forces. There have been some "predictions" generated by SM, but only in cases where there is an apparent symmetry with one type of particle "missing" it's symmetrical twin. The SM does not make true scientific predictions. It's not a theory. It's just a list of things we have observed. It's a model.

And because it's a model, it gets "reimagined" every time we discover something new. Since it's not a scientific theory, we don't have to make it make "sense" or work out the details for it. If we observe it, it goes in the SM. It represents what we know to be true, even if we don't understand it.

The reason why there is much interest in String Theory, and other Theories of Everything, is so that we can understand the "why" and "how" behind the SM. Why are there X numbers of elementary particle types and not more or less? Why does the [elementary particle] have THIS particular charge, spin and mass? etc, etc...

ST actually appears to offer explanations for these important questions. Even if we don't yet understand the answers, we can see that there IS a mechanism behind the curtain.

Hi Cyberia - can you help explain something to me? Is the current understanding that the universe did come from nothing? Or that nothing never existed, and that there was no "before" in which nothing could exist?

For nothing to be defined, doesn't it require something to exist alongside it?

Jeepers Creepers! Or maybe I should more aptly exclaim, "Holy Einstein!"

He wasn't even talking about the Standard Model! He was criticizing general relativity, the popular "model" or "theory" that has lead us to precisely zero technical or technological advancements over the nine decades since its introduction:

...looks like it might be accelerating. It has barely been more than ten years since that idea was thought idotic by most, because it conflicts with the previously established laws of gravity. Are you telling me that physicists can make such an enormous blunder as this, and still expect people to trust them...

All scientific theories change when new discoveries are made. This is true in every field of science...

And I agree completely. Practicing scientists use the word "theory" to refer to any tentative, evidence-based formulation potentially subject to experimental/observational confirmation, alteration or rejection, and carrying broad explanatory potential. Yet your and my view is flatly contradicted by the Bizarro World pedagogical definition from, for instance, the National Academy of Sciences -- a very unrealistic pedagogical definition with which I take issue and which delimits "scientific theory" to that which holds consensus, is supported by and in turn supports tangibly affirmed and affirmable evidence, and is unchanging. Again, this specialized definition only crops up in conjunction with arguments over evolution:

...The formal scientific definition of theory is quite different from the everyday meaning of the word. It refers to a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence. Many scientific theories are so well established that no new evidence is likely to alter them substantially...

Note that general relativity "theory" has been very plainly altered substantially through successive insertions, removals and reinsertions of an otherwise arbitrary cosmological constant thus with the desire of bringing it into approximate correspondence with the observables of the moment.

An interesting side-issue: Does "well established" general relativity predict gravitational waves? Most interpretations today say that general relativity supports the existence of gravitational waves. One of the most costly single-purpose projects of its kind ever undertaken is the half-billion dollar LIGO experiment, with a multi-billion dollar LISA in the works. LIGO hasn't found anything yet other than earthquakes and truck traffic. Einstein himself argued that gravitational waves do not exist:

...Einstein's frustration was in response to a paper titled "Do Gravitational Waves Exist?" that he had submitted to the Physical Review in 1936. The paper stated that gravitational waves do not exist.

The editor at the Physical Review had reservations about Einstein's theory and sent the paper to a referee. The paper was returned to Einstein with a critical review. Einstein wrote back to the editor expressing indignation, and the paper was subsequently published elsewhere...

(NB the proposal that gravitational waves do not exist is herein referred to as "Einstein's theory." Sloppy science writers!) A bit surprising isn't it that a "theory" so ostensibly well established as geometric gravitation could yet be so malleable and open to subjective interpretation that its own originator is somehow unclear about a fundamental prediction flowing from it two decades after its introduction? And of course as hideousmonster and I have pointed out, it seriously dropped the ball just a decade ago with the accelerating universe.

Hmm, Appeal To Authority? Do you also recommend that we skeptics of god get our heads screwed on straight by signing up for Goddidit101 at Liberty University? Seriously, although the pop press would have you believe that general relativity and Big Bang "theory" are secure as ever, a great deal of doubt within mainstream science has always lingered and continues to grow -- just leaf through Scientific American's coverage of MOND or its recent coverage of quantum gravity theories, for instance. Obviously if GR and BB were sound and complete scientific laws, there'd be no need at all for the ephemeral, unevidenced and physically nonproductive "angels dancing on pinheads" (i.e. curled up, hidden spacial dimensions) speculation that we see in things like string theory.

Hi Cyberia - can you help explain something to me? Is the current understanding that the universe did come from nothing? Or that nothing never existed, and that there was no "before" in which nothing could exist?

We can trace time back to 10-43 seconds after the BB. There is high confidence that we can understand events after this point, and no confidence that we can (currently) understand events prior to this. We need a theory of Quantum Gravity to look beyond this point. This is because during this initial period, gravitation effects were significant, if not dominant. Gravity doesn't just affect particles within spacetime, it affects the shape of spacetime itself. Prior to 10-43s at least two important events occurred: 1) spacetime was 'created' and 2) spacetime expanded RAPIDLY, an event known as Inflation. BOTH of these events are related to gravity and occurred in a miniscule universe, hence: Quantum Gravity is necessary.

Now, to answer your question, we don't know.

Current understanding indicates that "time" began at the instant of the BB, T=0. It is not though that this is a limit of our ability to look beyond this point, instead it is a literal beginning of time. There simply was no "before", figuratively or literally. QG will help us understand this issue.

We are also unsure if Conservation of Energy (Thermodynamics) is applicable to the BB or only after the BB. Conservation of Energy is definitely a property of our universe, but that doesn't mean it is necessarily valid "prior" to that or "outside" our universe. Without CoE, Nothing--->Something is most definitely possible.

He wasn't even talking about the Standard Model! He was criticizing general relativity, the popular "model" or "theory" that has lead us to precisely zero technical or technological advancements over the nine decades since its introduction:

He said Standard Model, if he misspoke or if I misunderstood, my apologies.

Now, for what you said, GR has brought about many technological advancements since it's introduction. GPS is one that comes to mind. Those satellites MUST account for relativistic effects or they will become useless within hours. Satellite based gravity maps of Earth wouldn't exist without GR. Communication with remote space probes is adjusted for GR, the space shuttle, the hubble telescope, earth based radar mappings of Venus and Mars must be adjusted for GR

He wasn't even talking about the Standard Model! He was criticizing general relativity, the popular "model" or "theory" that has lead us to precisely zero technical or technological advancements over the nine decades since its introduction:

Are you kidding? Wow. I don't know if it's worth responding to such stunning confident ignorance.

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Smart people believe weird things because they are skilled at defending beliefs they arrived at for non-smart reasons. --Michael Shermer

The history of religion is a long attempt to reconcile old custom with new reason, to find a sound theory for an absurd practice. --Sir James George Frazer

An interesting side-issue: Does "well established" general relativity predict gravitational waves? Most interpretations today say that general relativity supports the existence of gravitational waves. One of the most costly single-purpose projects of its kind ever undertaken is the half-billion dollar LIGO experiment, with a multi-billion dollar LISA in the works. LIGO hasn't found anything yet other than earthquakes and truck traffic. Einstein himself argued that gravitational waves do not exist:

...Einstein's frustration was in response to a paper titled "Do Gravitational Waves Exist?" that he had submitted to the Physical Review in 1936. The paper stated that gravitational waves do not exist.

Gravitational Waves are predicted by GR. As of 2008, they have not been detected directly. LIGO is only now starting to enter the predicted range of sensitivity to detect these wave, and it's very much at the bottom edge of that range.

There IS observational evidence that they exist however. Astronomers have located a pair of neutron stars orbiting each other at close range. As they orbit each other, the wavelength of the pulses varies exactly as predicted if gravitational waves exist. Furthermore, the frequency of the pulsar is very slowly decreasing, precisely as much as predicted if the waves are carrying away energy from the system. Hulse-Taylor binary.

Somewhat ironically for our discussion site here, one of these stars is possibly the "Star of Bethlehem".

Are you going to acknowledge that people shouldn't lie? hideousmonster made a specific claim, not about the validity of the Big Bang theory, but about HIS understanding of the evidence. When it comes to light that he hasn't actually even examined the evidence at all, just the opposite, in fact, he dismissed it without ANY examination on the grounds that it is "just" a mathematical proof, I think that demonstrates that he lied. Can you bring yourself to criticize him for being dishonest? I am quite willing to allow evidentiary concerns and I'm also willing to listen to concerns about utility, but I must insist that you cannot say you understand the evidence for the theory if you have specifically refused to even look at it. He cannot, even in broad strokes, offer ANY outline of the direction of the Hawking proof, much less offer specific criticism of it. He does NOT understand the evidence. The claim he made, I think, is incontrovertibly a lie.

He wasn't even talking about the Standard Model! He was criticizing general relativity, the popular "model" or "theory" that has lead us to precisely zero technical or technological advancements over the nine decades since its introduction:

Are you kidding? Wow. I don't know if it's worth responding to such stunning confident ignorance.

that is quite amazingly sad ignorance. trust1 should have his computer taken away from him for that idiocy. Go ahead and respond with the thought that some poor lurker is actually willing to think.

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"There is no use in arguing with a man who can multiply anything by the square root of minus 1" - Pirates of Venus, ERB

Here's an example sent to us by Hermes himself of practicing scientists referring to a scientific theory which yet does not at this early stage enjoy broad consensus nor is it "supported by a vast body of evidence." Again, in the real world a scientific theory is any tentative, evidence-based formulation potentially subject to experimental/observational confirmation, alteration or rejection, and carrying broad explanatory potential:

Loop Quantum Cosmology - The universe may have come from ... the universe

...The theory that the recycled universe was based on, called loop quantum cosmology (LQC)...

...Now the theory is poised to make predictions we can actually test...

...LQC is in fact the first tangible application of another theory called loop quantum gravity...

...after more feverish mathematics, Ashtekar, Singh and Pawlowski solved the problem. Early versions of the theory described the evolution of the universe in terms of quanta...

...Physicist Claus Kiefer at the University of Cologne in Germany, who has written extensively about the subject, agrees. "It is really a new perspective on how we can view the early universe," he says. "Now, you have a theory that can give you a natural explanation for a singularity-free universe." He adds that while competing theories of quantum gravity, such as string theory, have their own insights to offer cosmology, none of these theories has fully embraced quantum mechanics...

...This is the first time that a theory is able to make predictions about what was happening prior to inflation...

...might make inflation unnecessary, thus removing what has essentially always been an add-on to standard cosmological theory...

...No wonder Rovelli is looking forward to upcoming experiments that could vindicate the theory...

Please note that it isn't just the science writers but the scientists themselves who use the term theory in its broadest popular sense.

...GR has brought about many technological advancements since it's introduction. GPS is one that comes to mind...

Let's be clear: GPS and its precursor navigation systems (Transit, Timation) were in no way inspired in their development by relativistic thinking. They were engineered through a long steady process of conventional technical evolution as military navigation and guidance systems.

Theoretical physicists were not able to predetermine by consensus relativistic SV clock offsets ahead of the first Block 1 series of GPS satellite launches in 1977. GR is a malleable theory and, unlike highly deterministic Newtonian dynamics, is quite open to subjective interpretation. It was only after empirical, space-based experiments to determine actual clock rates at the new gravitational potential that a prelaunch rate offset was incorporated into each space vehicle clock. That this offset is now said to agree with the predictions of special and general relativity is another example of legalistic dissembling wherein well-documented history is inverted and postdiction is claimed as prediction.

Let's be clear: GPS and its precursor navigation systems (Transit, Timation) were in no way inspired in their development by relativistic thinking. They were engineered through a long steady process of conventional technical evolution as military navigation and guidance systems.

Theoretical physicists were not able to predetermine by consensus relativistic SV clock offsets ahead of the first Block 1 series of GPS satellite launches in 1977.

Now who's backtracking? First you said it has brought about no advancements, now you're changing that to "It never predicted the clock offset" (which is FALSE anyway, it did predict the offset, it's just that the engineers didn't realize they needed GR in the first place, so they didn't bother to run the prediction. When the satellites didn't work as expected, they troubleshot it and realized GR predicted something other that what they expected.)

It was only after empirical, space-based experiments to determine actual clock rates at the new gravitational potential that a prelaunch rate offset was incorporated into each space vehicle clock. That this offset is now said to agree with the predictions of special and general relativity is another example of legalistic dissembling wherein well-documented history is inverted and postdiction is claimed as prediction.

Those experiments verified the predicted offset of GR. You can't have it both ways. If they hadn't tested it, you'd claim it was an untested theory. When they do test it, you complain that they had to empirically test their 'theory'.